TOKYO — U.S. Defense Secretary Chuck Hagel expects to visit China's sole aircraft carrier when he arrives in the country on Monday, a U.S. official said, in an unprecedented opening by Beijing to a potent symbol of its military buildup.

The official believed Hagel would be the first official visitor from outside China to be allowed on board the Liaoning, although that could not be immediately confirmed.

The planned carrier visit, which will come at the start of Hagel's three-day trip to China, was quietly approved by Beijing at Washington's request and had not been previously announced, the official said, speaking on condition of anonymity.

The 60,000-tonne Liaoning, a Soviet-era ship bought from Ukraine in 1998 and re-fitted in a Chinese shipyard, is seen as a symbol of Beijing's rapid naval modernization and ambition for greater global influence.

Hagel will fly to China's port city of Qingdao after a trip to Japan, and then head to a Chinese naval base. While there, he will visit the Liaoning, the U.S. official said.

Reporters traveling with Hagel were not expected to accompany him on the vessel.

The disclosure of the carrier visit came a day after Hagel said he would use his first trip to China as defense secretary to press Beijing to use its "great power" wisely and respect its neighbors, who have been put on edge by the country's growing assertiveness in Asia's disputed waters.

"Coercion, intimidation is a very deadly thing that leads only to conflict," he said at a news conference on Sunday at Japan's defense ministry.

"All nations, all people deserve respect."

China claims 90 percent of the 3.5 million sq km (1.35 million sq mile) South China Sea, which is believed to be rich in oil and gas. The Philippines, Vietnam, Malaysia, Brunei and Taiwan all claim parts of those waters.

Beijing has a separate dispute with Tokyo in the East China Sea over uninhabited islets that are administered by Japan. China's decision in November to declare an air defense identification zone in the area that includes those islands sparked protests from the United States, Japan and South Korea.

Hagel, in his talks in Japan over the weekend and last week at a gathering of Southeast Asian defense chiefs in Hawaii, has sought to reassure allies of the U.S. security commitment to the region and has promised frank discussions in Beijing.

China, in turn, has repeatedly urged the United States not to take sides in any of these disputes, and has watched warily as Washington moves to strengthen its military alliances in the region, especially with Tokyo and Manila.

Indeed, at a time when Washington has stepped up its military presence in the region as part of a strategic "pivot" toward Asia, China is building new submarines, surface ships and anti-ship ballistic missiles, and has tested emerging technology aimed at destroying missiles in mid-air.

The Liaoning is the first step in what Chinese state media and some military experts believe will be China's deployment of several locally built carriers by 2020.

While President Xi Jinping recently urged China's military leadership to work faster to get the carrier combat-ready, some Chinese analysts and parts of the state media appear keen to dampen expectations about the Liaoning, which went on its first training mission into the South China Sea late last year.

The Liaoning would serve as a training platform rather than a fighting weapon, some Chinese experts have said.

Considerable doubt also remains over when it will be fully operational. Earlier estimates of two or three years had grown rubbery, with some hints internally that it could stretch to a decade, some experts say.

Nevertheless, as China's military grows, the U.S. and Chinese navies are expected to increasingly bump up against each other in hot spots in the region.

They hope to build up a mutual understanding that can help avert confrontations in the future, and Hagel's visit to China marks another step in that direction.

The risks of a mishap were highlighted in December when the American guided missile cruiser USS Cowpens had to take evasive action in the South China Sea to avoid hitting a Chinese warship operating in support of the Liaoning.